Current view: Text account
Site description (2001 baseline):
Site location and context
Lake Itasy is located 10 km south-east of Analavory and 25 km north-west of Soavinandriana. It is a freshwater crater-lake with marshy areas in its southern and eastern parts, lying within a steep-sloped volcanic massif. It is permanent, with seasonal variations in the water-level, having an average depth of 4 m but reaching up to 10 m at its centre. The Andranomena and Mariandrano rivers feed the lake in the east, while the Lily river flows out of the lake. The lake receives a lot of sediment from the rivers and from the eroded adjacent slopes. There is marginal vegetation of reedbeds
Phragmites and clumps of
Cyperus (up to 2 m), and floating mats of the non-native water-hyacinth
Eichhornia. Submerged plants include
Ceratophyllum and
Potamogeton. Near the middle of the lake, there is dense vegetation of various very tall aquatic plants.
See Box and Tables 2 and 3 for key species. Forty-four species are known from the lake, of which 10 are endemic to Madagascar. The dense vegetation near the middle of the lake is a refuge for herons (Ardeidae) and rails (Rallidae). A locally resident population of
Anas melleri is probably of national importance.
Ardea humbloti is infrequently recorded.
Pressure/threats to key biodiversity
The escarpments around the lake are completely bare of vegetation as a result of bush-fires and agriculture, and the significant erosion that ensues is accelerating the silting-up of the lake.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Lake Itasy (Madagascar). Downloaded from
https://datazone.birdlife.org/site/factsheet/lake-itasy-iba-madagascar on 23/11/2024.
